Interaction Among Living Things

Interaction Among Living Things Introduction 1. A place where organisms live in is called a habitat. Examples of habitat are forests, sea, ponds and wetlands. 2. A community is made up of several populations of organisms living together in a habitat. For example, a population of lions living together with a population of deer and zebra the same habitat. 3. The organisms are inter-dependent among themselves for food. 4. Some animals live in groups, while others live in solitary.

Group animals and solitary animals animals 1. Animals in their habitat either live in groups or are solitary. 2. Animals get certain advantages by living in groups or being solitary.

Animals that live in groups 1. Group animals are animals that live together with other members of their species in a habitat. 2. They live and hunt for food together. 3. Examples of animals that live in groups are zebras, penguins, monkeys, lions, ants and swallows.

Animals that lives in groups

4. Advantages of animals that live in groups. (a) They can cooperate to hunt for food. (b) They can help each other to defend themselves from enemies. (c) They can help each other to build their nest.

Animals that are solitary 1. Solitary animals are animals that live and hunt for food alone. 2. Some animals mark their territory by making scent marks or scratch marks on the tree trunk. 3. They only come together for mating. 4. Examples of animals that are solitary are the polar bear, tiger, koala bear, leopard and eagle.

Animals that are solitary

5. Advantages of solitary animals: (a) They can avoid competition for food. (b) They can avoid competition for space.

Competition is a form of interaction among living things. 1. Living things interact with one another in their habitat. 2. Living things interact to obtain basic needs such as water, food, space (shelter) and a mate for breeding. 3. Living things that share the same habitat normally interact with one another. 4. Competition is a form of interaction among living things in a habitat. 5. Competition exists when the basic needs of living things become limited. More than one species can compete for the same basic needs. For example, a lion will have to compete with a cheetah for food such as a zebra.

6. Competition also exists between animals of the same species. During the dry season, zebras compete with one another for water. 7. Interaction takes place in the form of food chains and food webs, which consists of: (a) producers - plants that make their own food. (b) consumers- animals that eat other animals or plants. (c) prey- animals that are eaten by other animals. (d) predators- animals that eat other animals. 8. Competition may involve animals of the same species or different species. 9. Competition can exist in two forms: (a) inter-species (competition involving different species) (b) intra-species (competition among the same species)

A lion and cheetah fighting for food 10. When competing, the stronger animal wins, while the weaker one gets killed or is chased away. 11. Competition happens among animals when: (a) there are limited food resources. (b) water is limited (c) they want the same mate during the breeding season (d) they share a habitat (e) they try to defend or establish their living space or territory 12. Basic needs that animals compete for include: (a) food (b) water (c) a mate (d) shelter (e) territory/space

13. Competition becomes greater or more intense when: (a) the number of animals fighting for the same basic needs increases, for example, When the number of elephants in habitat increases. (b) the basic needs that the animals compete for decreases, for example, during a drought when many plants die due to insufficient water. 14. When competing, the weaker animal will lose. The defeated animal will: (a) lose a place for shelter (b) lose the opportunity to reproduce (c) lose their source of food. Competition Among Plants 1. Plants compete for sunlight, water, nutrients and space. 2. Competition among plants becomes more intense if more plants grow in an area. 3. The effects of competition among plants include. (a) Each plant will try to grow taller to get enough sunlight. (b) The growth of plants that fail in competition will be retarded.

Plants compete for sunlight, water, nutrients and space

EXPERIMENT Aim To investigate competition among seedlings.

Materials and apparatus Petri dish, green beans, cotton wool, spoon and water.

The thing that 1. Is kept the same: amount of water and sunlight that is present 2. Is changed: number of seedlings in each dish. 3. Is measured: the growth rate of the seedlings.

Steps 1. The cotton wool is soaked with water. 2. The two Petri dishes are labeled as M and N. 3. Three beans are placed as far apart as you can in the Petri dish labeled M. 4. Ten beans are placed into the Petri dish labeled N. 5. Both the Petri dishes are placed near an open window. 6. The cotton wools are kept moist with water daily. 7. Record your observation.

Observation

1. Are the stems of the seedlings in Petri dishes M and N of the same size? Why? No, the seedlings in Petri dish M have thicker stems than the seedlings in Petri dish N because they get enough basic needs and need not compete among themselves. 2. Are all the seedlings in Petri dish N of the same height? No, the seedlings are of different heights. Discussion What do you think caused the seedlings to grow differently? The need to compete for the limited basic needs in the Petri dish. Conclusion Plants need to compete with each other when basic needs become limited.

Protecting endangered species Extinction of animals 1. Extinct means not in existence in the Earth anymore. 2. A species of animals become extinct when all of the species dies. 3. Examples of animals that are extinct are the dinosaur, dodo bird, Tasmanian wolf and auk bird.

Tasmania wolf

Auk bird

Dodo bird

Dinosaur

4. The dinosaur become extinct because of the change in climate and weather on the Earth. 5. The dodo bird and Tasmanian wolf become extinct because of human activities such as excessive hunting and destruction of their habitats.

Endangered species 1. Endangered species are species of animals or plants that are facing the threat of becoming extinct. 2. Examples of endangered species of animals are the orang utan, rhinoceros, blue whale, African elephant, tapir and giant panda.

Orang utan

Rhinoceros

Giant panda

African elephant

3. Examples of endangered species of plants are the rafflesia and pitcher plants.

Rafflesia

Pitcher plants

4. Human activities that cause the species to become extinct include: (a) illegal and excessive logging (b) illegal and excessive hunting (c) excessive development. Illegal and excessive logging 1. Illegal logging includes activities such as logging without license and logging outside licensed area. 2. Illegal and excessive logging cause many species to become extinct because their habitats are destroyed.

Habitat destroyed because of illegal and excessive logging.

Illegal and excessive hunting. 1. Illegal hunting causes animals that produce only one or few offspring to be threatened with extinction. 2. The table below shows examples of animals that are commonly hunted by humans.

Excessive Development 1. Many forest areas are developed into forms or residential areas. 2. The development destroys many habitats and causes a large number of species to become extinct. Ways to prevent the extinction of animals and plants. 1. Organizing campaign against excessive logging. 2. Avoid consuming or buying product made from endangered species. 3. Enforcing the law.

Impact of human activities on the environment 1. Human being carries out many types of activity. 2. Some activities are beneficial to mankind, while others may cause destruction to the environment. 3. Unplanned development may cause destruction to the environment through: (a) erosion (b) landslides (c) flash floods (d) water pollution (e) air pollution

Landslides

Flash floods

4. If humans do not plan their development activities properly, the following problems may arise: (a) living things will not be able to get their basic needs. (b) The balance is nature is disturbed (c) Human will be lose their source of medicinal herbs, building materials, fuel and Material for clothing. (d) The loss of the Earth's natural water basin. (e) Changes to the Earth's temperature. 5. Living things need oxygen in order to survive. When living things carry out respiration, carbon dioxide is released into the atmosphere. 6. Plants absorb the carbon dioxide and release oxygen back into the atmosphere during photosynthesis. Thus, it maintains the balance in nature. 7. If forest is cleared and the number of plants decreases, it will disturb the balance in nature.

8. During respiration, the oxygen level in the air decreases, while the carbon dioxide level increases.

9. The surface of the land and the soil beneath it are protected by plants from direct exposure to the rain. 10. The soil particles are held together by the roots of plants. Hence, they are not easily washed away by rain water. 11. Soil particles exposed to rain water will be washed away. This causes soil erosion, which result in landslides and floods. 12. The flood water carries silt down to lower lands and clogs up rivers and drains, or may flow to housing areas. 13. Soil erosion, landslides and floods expose humans and their properties to danger.

Steps to reduce destruction of the environment. (a) Enforcing law to stop illegal and excessive logging. (b) Planting new trees after logging. (c) Planning the development properly.